Comparison of Climate between Suzhou and Nanchang

Apart from human and economic factors, I think Nanchang is good, with clear skies and Wan Li, blue sky and white clouds. In Suzhou, it is basically gray for 360 days a year.

Suzhou climate

Suzhou is located in the north subtropical humid monsoon climate zone, which is warm, humid and rainy, with obvious monsoon, four distinct seasons, long winter and summer and short spring and autumn. The average frost-free period of a year is 233 days. Due to the differences in topography and latitude, various unique microclimates have formed in the territory. Solar radiation, sunshine and temperature are centered on Taihu Lake, and the areas along the Yangtze River are low-value areas. The distribution of precipitation also has the same law. The daily average temperature ranges from 7.5℃ to 8.2℃ in spring, followed by 7.7℃ in autumn, 7.5℃ in winter and 6.9℃ in summer. The maximum daily temperature difference is 8.5℃ in April. But in July and August, it is the smallest, which is 6.8℃.

Suzhou people's clothes are ordinary, casual and colorful. You only need to wear comfortable, casual and convenient clothes when traveling. Of course, the seasonal changes in Suzhou are also obvious. 65438+ 10, the monthly average temperature is 2-3℃, and the July average temperature is 28℃. Therefore, if you come here in early spring or late autumn, you'd better prepare a winter coat to prevent the surprise cold.

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General situation of Nanchang climate

I. Geographical location

Nanchang is located in the north-central part of Jiangxi, with an east diameter of about11527' ~1635' and a north latitude of about 2810' ~ 291/kloc-0'. Among them, the urban area is located between 28 35' ~ 28 55' north latitude and115 38' ~16 03' east longitude. Located in the lower reaches of Ganjiang River and Fuhe River, near the southwest bank of Poyang Lake, the largest freshwater lake in China; Flat terrain, dotted with lakes, the city's plain area of 26,565,438 0.79 kilometers, accounting for 35.8% of the total area; The water system area is 2 146.04 square kilometers, accounting for 29.0%; The northwest of the city is dominated by hills, with a mountainous area of 87.2 1 km2, accounting for 1.2% of the city's total area, and a hilly area of 879.62 km2, accounting for1.9%. Land area 1637.7 km2, accounting for 22. 1%.

In the total area of the city, 70% of the land has been developed except the water area. Among them, the cultivated land area is 4.02 million mu, accounting for 36.24% of the total area; Garden 69,000 mu, accounting for 0.62%; Woodland 1.6 million mu, accounting for14.4438+0%; The land for urban and rural residents and industrial and mining workers is 667,000 mu, accounting for 6.01%; The traffic land is 450,000 mu, accounting for 4.07%. When the five items are added up, * * * accounts for 6 1.35% of the city's total area.

Second, the general situation of climate

1, climate characteristics of Nanchang

Nanchang is located in the subtropical zone of the northern hemisphere and influenced by the East Asian monsoon, forming a subtropical monsoon climate. The city is rich in heat, abundant in rain and sunshine, and the rain and heat match well in the peak season of crop growth, which provides favorable meteorological conditions for agricultural production and is known as the land of plenty. However, due to the difference of monsoon intensity and advance and retreat in the morning and evening, the temperature changes greatly, the precipitation distribution is uneven, and meteorological disasters such as high temperature drought, low temperature chilling injury, rainstorm and flood occur frequently, which has adverse effects on people's production and life.

Temperature Nanchang has a mild climate, with an average temperature of17.1~17.8℃, and a cumulative temperature of ≥0℃ of 6256 ~ 6530℃. The temperature varies greatly, with the extreme maximum temperature above 40℃ in midsummer and the extreme minimum temperature below-10℃ in midwinter.

There is abundant rainfall in Nanchang, with an average rainfall of 1567.7 ~ 1654.7 mm over the years. The distribution of precipitation is uneven, and the rainfall from April to June in flood season accounts for about half of the annual rainfall; The interannual precipitation varies greatly, with the maximum reaching more than 1 time, the maximum rainfall reaching 2356 mm at 1954, and the minimum rainfall reaching 1046 mm only at 1963.

Nanchang is sunny. The average sunshine hours over the years are 1772 ~ 1845 hours, with the most in July and August and the least in February and March. The light distribution is basically synchronized with the peak season of crop growth, which is beneficial to agricultural production.

Solar radiation Nanchang is the secondary station of solar radiation observation, which carries out total radiation and net radiation observation. The average total radiation from 1986 to 2003 was 4279.02 MJ/m2, and the average net radiation from 1992 to 2003 was 2078.67 MJ/m2.

Fengnanchang is located in the monsoon climate zone, near Poyang Lake, and is rich in wind energy resources. Because the wind is greatly influenced by topography and geographical location, Nanchang, Xinjian and Jinxian are close to Poyang Lake, and the wind is strong, which belongs to the wind energy utilization area; Anyi is not near Poyang Lake, except for the special terrain and small wind, which has no use value.

2. Seasonal characteristics According to the standard of climate division and the statistical analysis of historical climate data, Nanchang has the characteristics of short spring and autumn and long summer and winter. Although the four seasons are different in length, the seasonal characteristics are obvious: warm and humid in spring, hot and rainy in summer, cool and dry in autumn and cold and little rain in winter.

Third, the disastrous weather in Nanchang

1, Rainstorm The rainy season in Nanchang generally starts in early April and ends in early July, lasting about 3 months. However, the length of rainy season and precipitation vary greatly in different years. The shortest rainy season 1987 is only 67 days, and the longest rainy season 1 19 days, a difference of 52 days. The rainy season 1954 maximum precipitation 1755mm, 1990 minimum precipitation is only 449mm, with a difference of1306 mm. According to the statistical analysis of 195 1 ~ 2003 rainy season precipitation data, serious floods occurred in Nanchang for eight consecutive years (1954, 1962, 1973, 1983,/kloc). Generally, it has been flooded for 8 years (1952, 1955, 1969, 1970, 1975, 1977, 1989) Except for a few years such as 196 1 and 1990, there are different degrees of rain and flood disasters almost every year.

2. Drought refers to a meteorological disaster with less precipitation for a long time, which leads to dry air and water shortage in soil, which affects the normal growth and development of crops and reduces yield. Severe drought will also cause rivers to dry up, making it difficult for people and animals to drink water. Drought occurs frequently in Nanchang in summer and autumn, but it is rare in spring and summer. According to the statistical analysis of1951~ the precipitation data in summer and autumn in 2003, Nanchang experienced severe drought for seven consecutive years (1958, 1963, 1966, 1974,1974.

3. From mid-March to mid-April, cold and warm air masses alternately affect the south of the Yangtze River, which is an important season for sowing and seedling raising of spring sowing crops such as early rice, cotton and vegetables. According to the statistics of Nanchang meteorological data from 195 1 to 2003, the frequency of "late spring cold" is 60%, of which severe "late spring cold" accounts for 40%, and it appears many times in some years, such as 1987, with a maximum of 5 times, 10. The "late spring cold" has a frequent influence on early rice sowing and seedling raising and cotton and vegetables sowing and seedling raising in Nanchang area, which is harmful.

4. Xiaoman cold appeared in late spring and early summer (around Xiaoman solar terms). The occurrence period is from late May to mid-June. At this time, it is in the stage of young panicle differentiation of early rice, and the appearance of "small full cold" will hinder young panicle differentiation, resulting in short panicle, spikelet or small grain, thus reducing yield. According to meteorological statistics, Nanchang has only seven years (195 1 ~ 2003, 1959, 1975, 1978, 1984,1). Therefore, the frequency of Nanchang's "Little Man Han" is not high, and its influence is not great.

5. The occurrence period of cold dew wind is from mid-September of 10 to early October of 10 (before and after the solar term). Mild "cold dew wind" mostly appears in the first half of September, which only affects the heading and flowering of early-maturing varieties of double-cropping late rice. Severe "cold dew wind" usually occurs from the late September of 10 to the early October of 10, which not only affects the heading and flowering of middle and late-maturing varieties of double-cropping late rice, but also hinders grain filling and fruiting, resulting in an increase in empty grain rate, a decrease in 1000-grain weight, a decrease in yield, and even no harvest in severe cases. According to19512003 Nanchang meteorological data, the frequency of "cold dew wind" is 52.8%, which occurs once every two years. Among them, the frequency of severe "cold dew wind" is 28.3%, about 1 time in 4 years. Therefore, the influence of "cold dew wind" on double-cropping late rice should not be underestimated.

6. Frost The frost in Nanchang first appeared in June+10 in 5438 and ended in April the following year at the latest. The average annual frost days are 18.9 ~ 29.2 days, with Nanchang being the least and Anyi the most. The average annual frost-free period is 255.7 ~ 276.2 days, with Anyi being the shortest and Jinxian the longest. The most frosty days are in 65438+February and 65438+ 10 in the following year. The first frost stops the growth of late autumn crops, and the last frost will affect the growth and development of early spring crops and even cause freezing damage.

7. Frozen winter is affected by the strong cold air from the north going south, which often brings snowfall and freezing weather, causing freezing damage to rape, vegetables, citrus and other fruit trees. According to the statistics of meteorological data, the average annual snowfall days in Nanchang area are 8 ~ 10 days, the snow days are 4 ~ 5 days, and the maximum snow depth is 20 ~ 40 cm. The freezing weather with daily minimum temperature below 0℃ mainly occurs from 65438+February to the following February. The lowest temperature is generally 0℃ ~-3℃, and the low temperature below -5℃ is only 1 ~ 2 days, and it can reach -7℃ ~-9℃ in some years. Low temperature below-10℃ is extremely rare. Combined with the analysis of freezing injury index of overwintering crops, rape, citrus and other crops sometimes suffer from freezing injury. For example, 199 1 winter, Nanchang was affected by strong cold air, and the lowest temperature was below -9℃, and the lowest temperature reached-12. 1℃, which caused the citrus to be seriously frozen, and some citrus reticulata was frozen to death, which had a great impact on citrus production. Judging from the geographical distribution of freezing damage, Anyi is relatively heavy, and Xinjian, Nanchang and Jinxian are less and lighter.

8. After the rainy season, controlled by the stable subtropical high, Nanchang often has continuous sunny and hot weather. If the daily average temperature is ≥30℃ and the daily maximum temperature is ≥35℃ for more than 5 days, high temperature and heat damage will occur. High temperature and summer heat not only endanger people's lives and health, but also affect the growth and development of crops. Continuous high temperature leads to early maturity, insufficient filling, decreased 1000-grain weight and yield of early rice. According to the disaster index and the statistical analysis of meteorological data over the years, the frequency of forced ripening of early rice at high temperature in Nanchang is 22.6%, about 1 for four years, including four years (19,71,19,88,2008). Mildly occurred in 2 1 year, with a frequency of 40%. There is no high temperature hazard for only 8 years, accounting for about 15%. Therefore, it is very necessary to take heatstroke prevention and cooling measures in extremely hot period.

9. A storm with a wind force of 8 (equivalent wind speed 17.2 ~ 20.7 m/s) is called a gale. Strong winds not only affect traffic safety, but also cause disasters to people's production and life to varying degrees. There are cold air gale and thunderstorm gale in Nanchang, and the annual average gale days are 2.6 ~ 12.4 days, with Nanchang being the most and Anyi the least. Although the probability of occurrence is not high, the harm should not be underestimated.

10, hail disaster Hail is a strong convective weather. Although the probability is small and the duration is short, it is very destructive, causing serious harm to people's lives, property and crops. According to the statistics of meteorological observation data, the average annual hail days in Nanchang area are only 0.2 ~ 0.3 days, with 1 time in about 3 ~ 5 years, mostly in March and April. Shigang and Xishan in Xinjian County often occur.

1 1. Lightning strikes Nanchang is a lightning-prone area with an average annual thunderstorm day of 50-60 days. There are thunderstorms every month of the year, but the most frequent period is from March to September. According to the incomplete statistics of the provincial lightning protection center, from 1998 to 2002, there were 50 lightning strikes in Nanchang, of which 15 was the most, causing different degrees of property losses and some casualties.